Dolichyl Phosphate Mannosyltransferase Polypeptide 3 (DPM3)

Dol-P-Man serves as a donor of mannosyl residues on the lumenal side of the endoplasmic reticulum (ER). Lack of Dol-P-Man results in defective surface expression of GPI-anchored proteins. Dol-P-Man is synthesized from GDP-mannose and dolichol-phosphate on the cytosolic side of the ER by the enzyme dolichyl-phosphate mannosyltransferase. The protein encoded by this gene is a subunit of dolichyl-phosphate mannosyltransferase and acts as a stabilizer subunit of the dolichyl-phosphate mannosyltransferase complex. The predicted 92-amino acid DPM3 protein contains 2 putative N-terminal transmembrane domains and a hydrophilic C-terminal portion. It shares 25%, 31%, and 97% amino acid identity with the C. elegans, S. pombe, and rat Dpm3 proteins, respectively.